The present invention generally relates to an apparatus for transferring pouches from a pouch conveyor into the product buckets of a cartoner. Specifically, the invention is an improvement of the transfer mechanism disclosed and claimed in U.S. Pat. No. 4,043,442 to Greenwell et al. ('442) which is assigned to the assignee of the present invention. U.S. Pat. No. 4,043,442 is fully and expressly incorporated by reference herein.
Both Greenwell '442 and the present invention are concerned with apparatus and process for transferring pouches from a form, fill and seal machine or poucher into the product buckets of a cartoner. Generally this was accomplished, by Greenwell, by oscillating ends of pouch conveyors back and forth laterally and intermittently feeding shingled groups of pouches into cartoner buckets moving constantly past the oscillating conveyor ends.
In the Greenwell '442 patent multiple lanes of pouches were fed onto a transfer apparatus which included a pair of slow conveyors at its upstream end and a pair of relatively faster conveyors at its downstream end. Respective slow and fast conveyors had overlapping portions and in that overlap location Greenwell et al. provided a check and release mechanism. The check and release mechanism not only provided an initial compacting of the shingled pouches but also held each shingled group momentarily until the associated fast conveyor had its upstream end raised to engage the shingled group to convey that group away from the check and release mechanism. The higher speed of the fast moving downstream conveyor effected the longitudinal separation of one group of shingled pouches from the next incoming group of shingled pouches on the adjacent conveyor. The overlapping conveyors provided assurance that the entire group of shingled pouches moved together when the fast conveyor was raised to engage them and carry them forwardly.
At the downstream end of the conveyor apparatus, Greenwell provided a second check and release mechanism. The second check and release mechanism stopped the oncoming group of shingled pouches until two side-by-side groups of shingled pouches were at the downstream end of the conveyor apparatus. When the two groups were assembled, the transfer mechanism was operated to swing alongside and in register with the product buckets and the check and release mechanism released the pouches. The fast moving conveyors then thrust or propelled the two groups of shingled pouches from the conveyors into the product buckets, one pouch in the shingled group following another. Immediately thereafter, the check and release mechanism returned to a check condition to capture the next group of shingled pouches. Because of the longitudinal spacing of the shingled pouch groups, imparted to them by the combined action of the slow and fast conveyors, there was a space interval between the incoming pouch groups which provided time for the check and release mechanism to operate.
The downstream check and release mechanism and the means for oscillating or swinging the conveyor apparatus were driven directly from the cartoner so that the release of the pouches was always in timed relationship to the movement of the bucket conveyor of the cartoner. Pouches were projected into buckets in momentary register with the oscillating ends of the conveyors. The pouch forming machine was also driven in timed relation to the bucket conveyor of the cartoner and the flow of pouches from the pouch forming machine coincided with the transfer of pouches into the product buckets of the bucket conveyor.
While the prior Greenwell apparatus provided a successful apparatus and process for loading shingled pouches into moving product buckets, packagers are now requiring increased speeds and cartoning efficiencies demanding faster bucket conveyor speeds. The Greenwell transfer or conveyor mechanism, and specifically the downstream check and release mechanism, has inherent limitations that prevent the use of such higher bucket conveyor speeds.
The downstream check and release mechanism disclosed in Greenwell '442, together with the serial ejection of pouches, necessitated a relatively long period of time to transfer the shingled groups of pouches from the end of the pouch conveyor into the product buckets. This period of time was directly related to the amount of time that it took the fast conveyor to discharge a shingled group of pouches, one pouch after another, into the product bucket. During the entire duration of the ejecting action, the end of the oscillating pouch conveyor had to be aligned or registered with a moving product bucket. The oscillating stroke length of the pouch conveyor was thus extended as a function of the time necessary to propel a shingle of pouches into the moving product bucket.
As used herein, the term "operating stroke" refers to that part of the oscillation cycle in which the free end or discharge end of the pouch conveyor is moving in registration with a particular product bucket of the bucket conveyor. The operating stroke therefore excludes those portions of the stroke in which the pouch conveyor is accelerating to reach the speed of the bucket conveyor, decelerating after release of the shingled pouches, and in reversing, accelerating, returning and decelerating to the beginning of the acceleration motion for in register ejection of pouches.
Also, the relatively long stroke of Greenwell's pouch conveyor caused the pouch conveyor to be at a proportionally large angle deviating from the perpendicular to the bucket conveyor as the shingled pouches were thrust or discharged into the product buckets, particularly at the beginning and end of the pouch ejection. This angular relationship has the capacity to cause misfeeding of pouches into buckets, particularly when operating at higher cartoning speeds. This, coupled with the inherent timing sensitivity of the downstream check and release mechanism, necessitated great accuracy in setting up and timing the transfer mechanism to run smoothly, and to insure that pouches were properly aligned in the product buckets.
Finally, Greenwell '442 provides no mechanism for rejecting single pouches or nonconforming groups of pouches between the pouch conveyor and the product buckets during the operation of the pouch conveyor. Thus, if undesirable pouches, pouch weights, pouch counts or the like were present on the pouch conveyor of Greenwell '442 either the entire operation was shut down in order to correct the problem, or the product buckets were improperly filled.
Accordingly, it has been one objective of the invention to provide an improved transfer apparatus for stacking pouches in product buckets where the buckets are moving at higher speeds than heretofore achieved.
It has been another objective of the invention to improve the efficiency of the process for transferring pouches from an oscillating conveyor to respective moving product buckets.
It has been still another objective of the invention to provide for rejections of undesirable pouches or pouch groups from a pouch conveyor prior to filling product buckets therefrom, and without interrupting the pouch transfer and bucket filling operation.